In a breakthrough deal, the museum would turn over some allegedly looted antiquities. Rome is to lend pieces of comparable quality.

ROME — Moving to end a long and embarrassing dispute over scores of allegedly looted antiquities, the J. Paul Getty Trust reached a deal Wednesday to return to Italy "a number of very significant" pieces, including several masterworks, representatives for both sides said.

A joint statement released by the Getty and Italian officials did not say how many objects would be returned, nor which ones. But it did say that Italy would lend Roman and Etruscan objects to the Los Angeles-based Getty that are "of comparable visual beauty and historical importance."

The Italians have been demanding that the Getty return 52 items, including a prized 2,400-year-old limestone and marble statue of the goddess Aphrodite. Getty officials have recently acknowledged that there was evidence that some items in the museum were probably looted from Italian sites and should be returned, but have appeared less willing to relinquish the Aphrodite statue.

A final agreement "which will include mutual collaboration, research and the exchange of important antiquities" is expected to be concluded early in the summer, the statement added. Although the statement did not specify how the collaboration would work, the Getty, which is the world's wealthiest art institution, could be of substantial help to the Italians on art conservation and research.

A deal with the Getty would be the capstone in a campaign by Italy to end the smuggling of its vast trove of antiquities to the world's top museums and private collections, a clandestine operation that has spanned generations and continents.

Until recently, officials here acknowledge, Italy had turned a blind eye to such plunder. This year, the Italians reached a similar deal with New York's Metropolitan Museum of Art that involved the return of one of the Met's best-known antiquities. The Culture Ministry is in discussions with Boston's Museum of Fine Arts and the Princeton University museum for the return of suspect antiquities, and Italian authorities say they will be approaching other major American institutions.

The agreement with the Getty came on the third day of often-tense talks here. On Tuesday, discussions had seemed bogged down amid serious disagreements, but they shifted Wednesday, participants said.

The agreement must be ratified by the Getty's board of trustees. It also lacks the imprimatur of a key member of the Italian negotiating team, Maurizio Fiorilli, who has maintained the most hard-line, all-or-nothing stance among the Italian negotiators.

Fiorilli, an attorney for the Italian Culture Ministry, had said this week that 33 items would be added to the list of Italy's demands. Other participants said Wednesday, however, that the original 52 was the number under negotiation.

The deal Wednesday was reached only after Fiorilli left the negotiations for a medical appointment. It was not clear whether he would support the agreement or whether he could attempt to block it.

By contrast, Fiorilli's boss, new Culture Minister Francesco Rutelli, has been keen to reach an accord as a political victory early in his tenure.

"For us, the most important thing is that the Getty for the first time recognizes our demands," said a Rutelli spokesman, Filippo Sensi.

The broad outlines of the proposed deal hew to the terms of the accord between Italy and the Metropolitan, which in February agreed to return 21 pieces in exchange for loans.

As was true with the Metropolitan's agreement, the Getty's deal leaves many details unresolved. Among the "major issues" that remain, one source involved in the talks said, are the mechanism for exchanging items and how to determine which pieces Italy would lend to the Getty.

"We are not just arguing over objects, but we are working on a long-term relationship between the Getty and its natural partner, Italy, with respect to antiquities. That's really what the proposed agreement is about," Luis Li, an attorney negotiating on behalf of the museum, said Wednesday evening.

"It is not just about the exchange of objects, but the exchange and development of knowledge."

The statement said that Italy and the Getty would collaborate on joint exhibitions "which will maximize the potential of the newly renovated Getty Villa, the only art museum in the United States dedicated to the art and culture of ancient Italy and Greece."

The Italian promise to lend equivalent items to the Getty drew praise from outside experts.

"We are evidently going to be able to see the same number and quality of objects that we saw before," said Selma Holo, director of the International Museum Institute and the Fisher Gallery at USC.

"I think that Michael Brand is making a powerful mark for himself," Holo said, referring to the Getty Museum's recently appointed director. "The mark that he is making is cleaning up this mess.